Beggiatoa (bej-e-ah-to'ah)

A genus of the Schizomycetes and of the family Beggiatoceae, consisting of long, straight, unbranched filaments, which in the swarming stage are sometimes spiral, thicker than in the allied genus, heptothrix, and are also distinguished by their containing sulphur in the form of strongly refracting granules and by not being surrounded by an enclosing sheath. They are motile by means of an undulating membrane. The Beggiatoae po e the property of decomposing sulphur compounds with the evolution of hydrogen sulphid. They occur in both running and stagnant water which receives sewage or other refuse, in sulphur springs, upon mud, and upon animal and vegetable bodies. B. alba. 1. A species found in the waste water from sugar manufactories, tanneries, etc., and in sulphur waters, forming a white or yellowish white layer (the baregine or glairine of the French); in the adult state also found upon decomposing water plants and dead insects. The filaments vary in thickne from 1 to 5 ju.. They increase by division. 2. Var. marina. Syn.: B. Oerstedtii. A variety of B. alba distinguished from the ordinary kind by its occurrence in sea water, and by its smaller size (thickne only 2 /u. ). B. a rach no idea. A species occurring in swamp and sulphur waters forming thick jointed motile rods. B. mirabilis [Cohn]. A species occurring as a white layer in sea water, in sea mud, and on marine plants and decomposing animal substances, distinguished by its very great size. By septation, it is converted into almost isodiametric particles. B. roseopersicina. A species found frequently in excavations and pools, forming a red or violet covering. The filamentous form is like that of B. alba, and is distinguished from it only by its red color, due to the presence of bacteriopurpurin. [From the name of F. S. Beggiato, an Italian botanist.]